Make Appends after Delete visible.

Signed-off-by: Goutham Veeramachaneni <cs14btech11014@iith.ac.in>

block.go

@@ -242,7 +242,7 @@ func (pb *persistedBlock) Delete(mint, maxt int64, ms ...labels.Matcher) error {
 	ir := pb.indexr
 
 	// Choose only valid postings which have chunks in the time-range.
-	vPostings := []uint32{}
+	delStones := map[uint32][]trange{}
 
 Outer:
 	for p.Next() {
@@ -259,7 +259,12 @@ Outer:
 
 		for _, chk := range chunks {
 			if intervalOverlap(mint, maxt, chk.MinTime, chk.MaxTime) {
-				vPostings = append(vPostings, p.At())
+				// Delete only until the current maxtime and not beyond.
+				maxtime := chunks[len(chunks)-1].MaxTime
+				if maxtime > maxt {
+					maxtime = maxt
+				}
+				delStones[p.At()] = []trange{{mint, maxtime}}
 				continue Outer
 			}
 		}
@@ -271,7 +276,7 @@ Outer:
 
 	// Merge the current and new tombstones.
 	tr := pb.Tombstones()
-	str := newSimpleTombstoneReader(vPostings, []trange{{mint, maxt}})
+	str := newMapTombstoneReader(delStones)
 	tombreader := newMergedTombstoneReader(tr, str)
 
 	return writeTombstoneFile(pb.dir, tombreader)

head.go

@@ -250,7 +250,12 @@ Outer:
 			}
 		}
 
-		h.tombstones.stones[ref] = addNewInterval(h.tombstones.stones[ref], trange{mint, maxt})
+		// Delete only until the current values and not beyond.
+		maxtime := h.series[ref].head().maxTime
+		if maxtime > maxt {
+			maxtime = maxt
+		}
+		h.tombstones.stones[ref] = addNewInterval(h.tombstones.stones[ref], trange{mint, maxtime})
 	}
 
 	if p.Err() != nil {

head_test.go

@@ -382,7 +382,7 @@ func TestHeadBlock_e2e(t *testing.T) {
 	return
 }
 
-func TestDelete_simple(t *testing.T) {
+func TestDeleteSimple(t *testing.T) {
 	numSamples := int64(10)
 
 	dir, _ := ioutil.TempDir("", "test")
@@ -474,6 +474,39 @@ Outer:
 	}
 }
 
+func TestDeleteUntilCurMax(t *testing.T) {
+	numSamples := int64(10)
+
+	dir, _ := ioutil.TempDir("", "test")
+	defer os.RemoveAll(dir)
+
+	hb := createTestHeadBlock(t, dir, 0, 2*numSamples)
+	app := hb.Appender()
+
+	smpls := make([]float64, numSamples)
+	for i := int64(0); i < numSamples; i++ {
+		smpls[i] = rand.Float64()
+		app.Add(labels.Labels{{"a", "b"}}, i, smpls[i])
+	}
+
+	require.NoError(t, app.Commit())
+	require.NoError(t, hb.Delete(0, 10000, labels.NewEqualMatcher("a", "b")))
+	app = hb.Appender()
+	_, err := app.Add(labels.Labels{{"a", "b"}}, 11, 1)
+	require.NoError(t, err)
+	require.NoError(t, app.Commit())
+
+	q := hb.Querier(0, 100000)
+	res := q.Select(labels.NewEqualMatcher("a", "b"))
+
+	require.True(t, res.Next())
+	exps := res.At()
+	it := exps.Iterator()
+	ressmpls, err := expandSeriesIterator(it)
+	require.NoError(t, err)
+	require.Equal(t, []sample{{11, 1}}, ressmpls)
+}
+
 func TestDelete_e2e(t *testing.T) {
 	numDatapoints := 1000
 	numRanges := 1000